I only have a modest familiarity with Smith's work, but I am a great admirer. I like best her economy and subtlety. Her writing, like that of Carl Sandburg* often uses plain language that makes it readily accessible at the surface, which makes it all the more likely that we'll stick with it to see what lies below. (For those who immediately notice the parallel with Matt Groening, there's even more: Smith often adds her own cartoons to the poetry.)

Said better, here are some of the back-cover notes from the publisher:

Stevie Smith wrote poems about everything -- hats, children, death... friends, foes, and animals... in an inimitable way. ...themes that at first seem simple, almost childlike, cut knife-edge deep to serious concerns;... her mischievous throw-away lines are sly in their subtle control; her humor...is a coin with a dark side.

Go read some. I think you'll be both happy and sad if you do.**

Notes:

* Do click the link.

** Erika L., I think that you, in particular, would enjoy this writer (if you haven't, already(!)).